The invention is directed to a fastening means for a transformer module and a signal generator for mounting at a signal tower. Fastenings for signal generators at a signal tower are known. German Utility Model G 89 02 750 discloses a combined mount that serves the purpose of fastening a signal generator to a signal tower for traffic light signal systems.
Since traffic light signal systems are being decentralized to an increasing degree and are operated with low-volt technology, it is required to undertake the voltage conversion in the region of the signal generator. In low-volt technology, a separate transformer having a corresponding fastening was arranged in the respective signal generator chamber for every chamber, as disclosed, for example, in German Utility Model G 87 15 847. A separate post block or terminal block having plugs was respectively required per light signal generator chamber for that purpose (German Utility Model 87 15 848). In such traffic signal systems, the cabling ensued star-like from the node control means to the respective signal towers or, respectively, signal generators.
German published application DE-OS 32 30 761 already discloses a traffic signal system wherein every signal generator is fed via a single two-lead line and is supplied with a separate control line for switching the individual signal lamps. The installation therein disclosed is designed to reduce and simplify the cables required, particularly at junctions and traffic control points with numerous traffic signal units. Each unit (1, 2) contains in a single housing the customary red (3) green (4) and amber (5) lamps, each of which is connected (11) through an individual switch (7) to the secondary side of a transformer (8) and also to a switching instrument (12). The transformer steps down the main voltage to a suitable voltage in the range 6 to 60 volts for the lamps. The switching instrument in each unit operates the lamp switches (7), receives switching signals and delivers lamp power circuit status signals to the central control unit (6) through a connecting signal lead (13). Preferably the second lead of a dual-lead connection between the switching and control instruments is provided by the zero lead (10) of the dual-lead power connection to the unit. The transformer primary winding is coupled by wires (9, 10) to the main supply (14) and the transformer reduces the voltage to a 12 volt supply. Operation of the selected lamp is effected by commands from the control activating the switch stage (12). This disclosed system is thereby operated in low-volt technology.
In modern traffic light signal systems, a transformer should be provided for the voltage conversion, together with rectifier and appertaining components for a plurality of signal generators or, respectively, signal generator combinations, potentially for all signal generator combinations of a signal generator tower.